Overarm actuating mechanism



OCE. 15, 1940. F, A, HASVSMAN 2,218,469

OVERARM ACTUATING MECHANISM Filed July 3, 1959 //llI/IIIIIIIIIII// l' 6 INVENTOR.

ff///fJsm/Y ATTORNEY.

" act structural details there shown and described,

Patented oci. 1s, 1940 rATENT t OFFICE OVERARM ACTUATING MECHANISM Fred A. Hassman, Cincinnati, Ohio, assigner to The Cincinnati Milling Machine C'o., Cincinnati, Ohio, a corporation of Ohio Application July s, 193e, serial Nc. 282,652

7 Claims.

rlhis invention relates to machine tools and more particularly to improvements in milling machines. p

One of the objects of thisinvention is to provide an improved overarm structure'for milling machines. 1

A more specific object of this invention is to provide improved mechanism for shifting` and clamping the'overarm sup-port for milling mar-- chine spindles. i

Other objects and advantages of the present invention should be readily app-arent by reference to the following specification, considered in conjunction with the accompanying drawing forming 2t part thereof and it is lto be understood that any modifications may be made in the eawithin the scope of the appended claims, without departing from or exceeding the spirit of the invention.

Referring to the drawing in which like reference numerals indicate like or similar parts:

Figure l is a side elevation o-f a milling machine embodying the principles of this invention.

Figure 2 is an elevational view partly in section showing the actuating means for the overarm. i

Figure 3 is a section on the line 3--3 of Figure 2. v

Figure 4 is a section on the line fle-l of Figure 3. Figure 5 is a section on the line .1i-Enf Figure 4. I l

Figure 6 is asection similar to Figure 3 with the 4clutch in shifted position for actuation of the overarm clamp.

In Figure 1 of the dra-wingthere is illustrated `a knee and column type milling machine to which this invention is particularly adaptable and therefore will be described in connection therewith.

The reference numeral lil indicates the column of the machine upon the front face of which is. formed va vertical guideway I I for receiving and guiding a vertically movable knee I 2. The knee is `provided with horizontal guide surfaces I3 for a crosswise moving saddle It; and the saddle, in turn, is provided with a dovetailed guideway I5 on which reciprocates a work supporting table it.

This machine has a power driven spindle il for rotating an arbor I8 upon which is keyed a milling cutter or tool I9.` y

Means are provided for supporting the outboard end of the arbor comprising a pendant and an overarm 2l, The underside of the overnism for adjusting the overarm relative to the column, and for clamping the overarm to the column.

Referring to Fig-ure 3, the top of theV column isV provided with a dovetailed guideway, one guide vsurface 24 of which extends parallel to the axis `of the cutter spindle, and the other guide surfacey 25 of which', asshown in Figure 5, is non-parallel with the axis of the spindle, it being sufficiently spaced from the first guide to provide clearance for `a tapered gib 26 which is utilized to frictionally clamp theoverarm against the surface Z/l, thereby insuring that the overarm is clamped in such a position that its guide surfaces 22 and 23 extend parallel to the cutteil axis and thereby provide an accurate guide for the pendant 2u. p

The upper portion of the column Iil is provided with a bore 2l in which is mounted actuating mechanism for effecting selective operation ofthe overarm, or of the clamping mechanism. This bore intersects the bottom of the dovetailed guideway formed `in the top of a column, and

has mounted therein a pinion 2i which intermeshes withfrackteeth 28 formed on thebottom of the gib 2B, as more particularly shown in Figure 4, and a second pinion 29 which intermeshes with rack teeth 30 formed on the underside of the overarm as more particularly shown in Figure 2.

The pinions 29 and 21 are supported for free rotation on a shaft 3| which has a clutch member 32 secured to it between the pinions as by a tapered pin 33. l'I'he opposing ends of the pinions are provided with clutch teeth 34 and 35 for selective engagement rby clutch teeth formed on opposite ends of the clutch member 32.

The end of the bore 2l is closed by a sleeve 35 which serves to hold the parts in position and support the shaft 3l for rotation.` The sleeve is held in position. by a set screw 31.

The outer end of the shaft 3I has a hand wheel secured thereto as by a tapered pin 39 and this hand wheel serves for rotating the shaft as well as for shifting it axially for selective positioning of the clutch. The end of the sleeve 33 is counterbored at 40 to provide for a spring M located therein for continuously urging the shaft 3I in a direction toenormally maintain engagement of the clutch 32 with the clutch teeth 34 of the overarm actuating pinion 39. Thus, normal rotation of the hand wheel will eiect actuation of the overarm, whereas it is necessary to push in on the hand wheel and then rotate it to actuate the gib 26.

In operation, the operator eiiects engagement of the clutch 32 with the gib operating pinion 2l and then rotates the hand wheel to unlock the gib. By releasing the hand wheel the clutch automatically shifts into engagement with the pinion 29 whereby the hand wheel is rotated to effect the necessary or desired adjustment of the overarm.

The rst operation is then repeated with the exception that the pinion 21 is rotated the opposite direction to clamp the gib.

It will thus be apparent that a new, improved and simpliiied mechanism has been provided for adjusting and clamping the overarm ci a milling machine.

What is claimed is:

1. In a milling machine having a column, a cutter spindle journaled in the column and an overarm mounted on the top of the column for adjustment parallel to the axis of the spindle, said column having a guideway formed therein for receiving said overarm, the combination of a tapered gib supported in said guideway between one side of the overarm and the column, rack and pinion means vfor shifting said gib, a second rack and pinion means for shifting said overarm, an operating hand wheel and clutch means for operatively connecting said hand wheel for selective actuation of the respective rack and pinion mechanisms.

2. In a milling machine having a column, a cutter spindle journaled in said column and an overarm mounted on top of said column, the combination of means for shifting and clamping said overarm, said column having a depressed guideway formed in the top thereof for receiving said ov-erarm, a tapered gib mounted in said guideway between one side oi said overarm and the column, an operating mechanism for sluiting A the gib terminating in a iirst clutch member, an

operating mechanism for shifting the overarm and terminating in a second clutch member, an operating hand Wheel, a clutch operatively iiiied with said hand wheel for axia shifting or rotation thereby, and means normally maintaining said clutch in engagement with the last-named clutch member.

3. In a milling machin-e having a column, a cutter spindle supported in said column, an overarm mounted on top of the column or supporting the outboard end of a cutter arbor driven by the spindle,y the combination with a guideway formed in the column for receiving said overarm, a taper-ed gib slidably mounted in said guideway for movement parallel to the movement of said overarrn for clamping the overarm to the column, mechanical means for translating the overarm, additional mechanical means for shifting said gib, a hand wheel rotatively supported by the column, and` means for selectively connecting the hand wheel for operation of the respective mechanical means.

4. In a milling machine having a column, a cutter spindle supported in said column, an overarm mounted on top of the column for supporting the outboard end of a cutter arbor driven by the spindle, the combination with guideway means formed in the column for receiving said overarm, of a tapered gib mounted in said guideway means and movable axially thereof for clamping and unclamping the overarm, of rack and pinion means for actuating the gib, additional rack and pinion means for actuating the overarm, a hand wheel rotatably supported by the column, and means for selectively connecting the hand wheel with the respective rack and pinion means for sole actuation of either the gib or the overarm.

5. In a milling machine having a column, a cutter spindle supported in said column and an overarm mounted on top of the column for supternately shiftable into engagement with ther clutch teeth of the respective pinions, and means normally maintaining engagement of the clutch member with the clutch teeth of one of said pinions.

6. In a milling machine having a column, an V overarrn mounted on the column, and means for clamping the overarm to the column, the combination of a rst mechanical means for bodily shifting the overarm including a clutch pinion, a second mechanical means for operating the clamping means including a second clutch pinion, a manually operable member supported by the column, a clutch member integral with said member and interposed between the respective clutch pinions, and means normally maintaining the clutch in engagement with the clutch pinion which operates the overarm.

7. In a milling machine having a column, a cutter spindle supported in said column, an overarm mounted on top of the column for supporting the outboard end of a cutter arbor driven by the spindle, the combination with guideway means for the overarm, of a longitudinally shiftable tapered gib for clamping the overarm to the column, mechanical means for bodily shifting the overarm including an actuating member having clutch teeth formed thereon, a shiftable clutch member engaging said teeth, a shaft integrally connected to said clutch member, a inanually operable hand wheel iixed to said shaft, mechanical means for shifting said gib lincluding a` second pinion having clutch teeth formed thereon and positioned for engagement by said clutch member, and means normally maintaining the clutch member in operative engagement with the iirst-named pinion whereby axial and rotatable pressure must be simultaneously applied to said shaft to eiect actuation of said gib.

FRED A. HASSMAN. 

